It's a panorama viewer on steroids. I like it a lot.
They even offer a firefox plugin and it's smooth as can be.

They must have had a really smart approach on streaming imagery.

It does not give the same experience as a panorama viewer imho. A panorama
viewer can give you a real immersive feeling (provided your display is big
enough). The type of viewing of this viewer makes you much more eager to
start exploring a scene.

A thing it misses is an indication of the quality of a view. After zooming
in a few times in vain you might give up trying quickly.

serge.

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